9.
REPETITION AND
DISORGANIZATION
• Symptom: See many of the same declarations over and over.
• Symptom: See styles being overridden in web inspector.
• Symptom: Having to reset styles because of previous
declarations.

16.
HOW BROWSERS EVALUATE CSS
Resources:
https://developers.google.com/speed/docs/best-practices/rendering
https://developer.mozilla.org/en-US/docs/CSS/Writing_Efﬁcient_CSS
The engine evaluates each rule from right to left, starting
from the rightmost selector (called the "key") and moving
through each selector until it ﬁnds a match or discards the
rule. (The "selector" is the document element to which the
rule should apply.)

19.
NO FALLBACKS
• Know what you support, and debug before you see it in the
browser.
• Most common with colors, so add a simple color
(background-, border-) declaration fallback.
• Includes setting position properly -- a common problem in
some browsers